FENAL Multivitamins / Iron Capsule 1's
Indications/Uses
Dosage/Direction for Use
Administration
Contraindications
Special Precautions
Cyanocobalamin (Vitamin B12) should, if possible, not be given to patients with suspected Vitamin B12 deficiency without first confirming the diagnosis. Regular blood monitoring is advisable. Administration of Vitamin B12 doses greater the 10 μg daily may produce haematological response in patients with folate deficiency; indiscriminate use may mask the precise diagnosis. Conversely, folate may mask vitamin B12 deficiency.
Iron compounds should not be given to patients receiving repeated blood transfusions or to patients with anaemias not produced by iron deficiency is also present. Oral iron therapy should not be administered concomitantly with parenteral iron. Care should be taken in patients with iron-storage or iron-absorption diseases such as haemochromatosis, haemoglobinopathies or existing gastrointestinal diseases such as inflammatory bowel disease, intestinal structures and diverticulae.
Adverse Reactions
Folic acid - gastrointestinal disturbances and hypersensitivity reactions.
Iron - gastrointestinal irritation and abdominal pain with nausea and vomiting, diarrhea and constipation (side effects may be reduced by administration with or after food or by beginning therapy with a small dose and increasing gradually); iron overload may also occur with increased storage of iron in various tissues (haemosiderosis) as a result of excessive oral or parenteral therapy since absorbed iron is conserved by the body, as well as patients suffering from iron-deficiency anaemia and those with pre-existing iron storage or absorption diseases.
Drug Interactions
Cyanocobalamin (Vitamin B12) absorption from the gastrointestinal tract may be reduced by neomycin, aminosalicylic acid, histamine-H2-receptor antagonists, and colchicine. Serum concentrations may be decreased by concurrent administration of oral contraceptives. Parenteral chloramphenicol may attenuate the effect of Vitamin B12 in anaemia.
Iron salts are not well absorbed by mouth, and administration with food may further impair their absorption. Compounds containing calcium and magnesium, antacids and mineral supplements, bicarbonates, carbonates, oxalates, or phosphates may also impair the absorption of iron by the formation of insoluble complexes. Absorption of both iron and tetracycline are diminished when they are taken concomitantly by mouth. If treatment of both drugs is required, a time interval of about 2-3 hours should be allowed between them. A suitable interval is also advised if an iron supplement is required in patients receiving trientine. Zinc salts may decrease the absorption of iron. On the contrary ascorbic acid and citric acid may actually increase the absorption of iron. Response to iron may be delayed in patients receiving systemic chloramphenicol. Iron salts can also decrease the absorption of drugs like bisphosphonates, entacapone, fluoroquinolones, levodopa, methyldopa, penicillamine and tetracycline thus, reduce their bioavailability and clinical effect. Iron salts may also reduce the efficacy of thyroxine (levothyroxine).
Storage
Action
Riboflavin (Vitamin B2) is absorbed from the gastrointestinal tract. Although riboflavin is widely distributed to body tissues, little is stored in the body. Vitamin B2 is converted in the body to the coenzyme flavine mononucleotide (FMN; riboflavin-5'-phosphate) and then to another coenzyme flavine adenine dinucleotide (FAD). About 60% of FMN and FAD are bound to plasma proteins. Vitamin B2 is excreted unchanged; crosses the placenta and is distributed in the breast milk.
Niacinamide (Vitamin B3) is readily absorbed from the gastrointestinal tract following oral administration and widely distributed in the body tissues. Niacinamide appears in the breast milk. The main route of the metabolism is its conversion to N-methylnicotiamide and the 2-pyridone and 4-pyridone derivatives; nicotinuric acid is also formed. Small amounts of Vitamin B3 are excreted unchanged in the urine following therapeutic doses; however the amount excreted unchanged is increased with larger doses.
Folic acid is rapidly absorbed from the gastrointestinal tract, mainly from the duodenum and jejunum. The naturally occurring folate polyglutamates are largely deconjugated and reduced by dihydrofolate reductase in the intestines to form 5-methyltetrahydrofolate, which appears in the portal circulation, where it is extensively bound to plasma proteins. Folic acid administered therapeutically enters the portal circulation largely unchanged. It is converted to the metabolically active form 5-methyltetrahydrofolate in the plasma and liver. The principal storage site of folate is the liver and it is also actively concentrated in the CSF. Folate undergoes enterohepatic circulation. Folate metabolites are eliminated in the urine and folate in excess of body requirements is excreted unchanged in the urine. Folate is distributed into breast milk. Folic acid is removed by haemodialysis.
Cyanocobalamin (Vitamin B12) binds to intrinsic factor, a glycoprotein secreted by the gastric mucosa, and are then actively absorbed from the gastrointestinal tract. Absorption is impaired in patients with an absence of intrinsic factor, with a malabsorption syndrome or disease or abnormality of the gut, or after gastrectomy. Absorption from the gastrointestinal tract can also occur by passive diffusion. After intranasal administration, peak plasma of Vitamin B12 have been reached in 1 to 2 hours. Vitamin B12 is stored in the liver, excreted in the bile, and undergoes extensive enterohepatic recycling; part of an administered dose is excreted in the urine, most of it in the first 8 hours; urinary excretion, however, accounts for only a small fraction in the reduction of total body stored acquired by dietary means. Vitamin B12 diffuses across the placenta and also appears in breast milk.
Iron is regularly and incompletely absorbed from the gastrointestinal tract, the main sites of absorption being the duodenum and jejunum. Absorption is aided by the acid secretion of the stomach and by some dietary aids (such as ascorbic acid) and is more readily affected when the iron is the ferrous state or is a part of the haem complex (haem-iron). Absorption is also increased in conditions of iron deficiency or in the fasting state but is decreased if the body stores are overloaded. Only about 5% to 15% of the iron ingested in food is normally absorbed.
MedsGo Class
Features
- Iron
- Multivitamins